1. Field of the Invention
The present invention relates to a method for judging a read error and an apparatus for judging whether an error has occurred when reading data recorded in recording portions provided in conformity with the respective frames of a photographic film.
2. Description of the Related Art
In recent years, advanced photosystems having a variety of standards have been put into practical use. A photographic film used in conjunction with this advanced photosystem is formed with magnetic recording portions corresponding to exposure areas of the respective frames so that information concerning the photographing such as a date of photographing and an exposure value (hereinafter, "photograph information") can be recorded as magnetic data by a recording means in a camera. The magnetic data recorded in the magnetic recording portions are read, for example, by a reading means provided in a photo-printing apparatus. Based on the read data, a character image of, e.g. the date of photographing is printed on a photographic paper and the printing is performed with a proper exposure condition set.
Some of the above photographic films are provided, in addition to the magnetic recording portions in which the photograph information is recorded, with magnetic recording portions in which information concerning printing (hereinafter, "print information") such as the number of prints to be made and a date of printing is so recorded by, e.g. a photographic film processing apparatus other than a camera such as a photo-printing apparatus in conformity with the respective frames. The magnetic data recorded in the latter magnetic recording portions are read by a reading means provided in, e.g. the photo-printing apparatus and a specified processing is performed based on the data read.
With the photographic film used in conjunction with the advanced photosystem, exposure may be freely stopped and started, i.e. it may be stopped after an intermediate frame or started from an intermediate frame. Accordingly, in the case the photograph information is recorded for the exposed frames without fail, the magnetic data may be recorded only up to an intermediate frame or only from an intermediate frame in the photographic film taken out of the camera after the photographing operation.
In such a case, if there is a frame whose magnetic data could not be read when the magnetic recording portions are subjected to relative scanning by the reading means of the photo-printing apparatus or the like, whether a read error has occurred or the magnetic data is not recorded cannot be judged. Accordingly, every time there is a frame whose magnetic data, including the photograph information and the print information, could not be read from the respective magnetic recording portions, necessary processing steps are performed later regardless of whether or not a read error has actually occurred.
On the other hand, it is also possible not to record the photograph information for the respective exposed frames. In such a case, the magnetic data is recorded in none of the magnetic recording portions for storing the photographing information. In this case as well, necessary processing steps are performed later assuming that an error has occurred when reading the magnetic data.
Thus, even if the magnetic data is not recorded and no read error has actually occurred, it is necessary to reread the data because of apprehension of a possible read error. This reduces operability during the printing operation. Further, although the magnetic data may be obtained by rereading the data if the read error has actually occurred, an occurrence of the read error is judged again if the magnetic data is not recorded. This may lead to apprehension that the apparatus may be defective.
In view of the above problems, an object of the present invention is to provide a method and an apparatus for accurately judging whether or not an error has occurred when reading data recorded in recording portions provided in conformity with the respective frames of a photographic film.